Systems and methods for providing real time security and access monitoring of a removable media device

ABSTRACT

In various embodiments, a method comprises detecting a removable media device coupled to a digital device, authenticating a password to access the removable media device, injecting redirection code into the digital device, intercepting, with the redirection code, a request for data, determining to allow the request for data based on a security policy, and providing the data based on the determination. The method may further comprise selecting the security policy from a plurality of security policies based, at least in part, on the password and/or filtering the content of the requested data. Filtering the content may comprise scanning the data for malware. Filtering the content may also comprise scanning the data for confidential information.

CROSS REFERENCE

This application is a continuation of U.S. nonprovisional patent application Ser. No. 12/622,386, entitled “Systems and Methods for Providing Real Time Access Monitoring of a Removable Media Device,” filed Nov. 19, 2009, which in turn claims benefit of U.S. provisional patent application Ser. No. 61/116,210, entitled “System and Method for Providing Real Time Access Monitoring of USB Flash Drive Without Resident Software,” filed Nov. 19, 2008. Both U.S. nonprovisional patent application Ser. No. 12/622,386 and U.S. provisional patent application Ser. No. 61/116,210 are hereby incorporated by reference.

TECHNICAL FIELD

This invention relates generally to computer security, and more particularly provides a system and method for providing data and device security between external and host devices.

BACKGROUND

The internet is an interconnection of millions of individual computer networks owned by governments, universities, nonprofit groups, companies and individuals. While the internet is a great source of valuable information and entertainment, the internet has also become a major source of system damaging and system fatal application code, such as “viruses,” “spyware,” “adware,” “worms,” “Trojan horses,” and other malicious code.

To protect users, programmers design computer and computer-network security systems for blocking malicious code from attacking both individual and network computers. On the most part, network security systems have been relatively successful. A computer that connects to the internet from within an enterprise's network typically has two lines of defense. The first line of defense includes a network security system, which may be part of the network gateway, that includes firewalls, antivirus, antispyware and content filtering. The second line of defense includes individual security software on individual machines, which is not typically as secure as the network security system and is thus more vulnerable to attacks. In combination, the first and second lines of defense together provide pretty good security protection. However, when a device connects to the internet without the intervening network security system, the device loses its first line of defense. Thus, mobile devices (e.g., laptops, desktops, PDAs such as RIM's Blackberry, cell phones, any wireless device that connects to the internet, etc.) when traveling outside the enterprise network are more vulnerable to attacks.

FIG. 1 illustrates an example network system 100 of the prior art. Network system 100 includes a desktop 105 and a mobile device 110, each coupled to an enterprise's intranet 115. The intranet 115 is coupled via a network security system 120 (which may be a part of the enterprise's gateway) to the untrusted internet 130. Accordingly, the desktop 105 and mobile device 110 access the internet 130 via the network security system 120. A security administrator 125 typically manages the network security system 120 to assure that it includes the most current security protection and thus that the desktop 105 and mobile device 110 are protected from malicious code. Demarcation 135 divides the trusted enterprise 140 and the untrusted public internet 130. Because the desktop 105 and the mobile device 110 are connected to the internet 130 via the network security system 120, both have two lines of defense (namely, the network security system 120 and the security software resident on the device itself) against malicious code from the internet 130. Of course, although trusted, the intranet 115 can also be a source of malicious code.

FIG. 2 illustrates an example network system 200 of the prior art, when the mobile device 110 has traveled outside the trusted enterprise 140 and reconnected to the untrusted internet 130. This could occur perhaps when the user takes mobile device 110 on travel and connects to the internet 130 at a cybercafé, at a hotel, or via any untrusted wired or wireless connection. Accordingly, as shown, the mobile device 110 is no longer protected by the first line of defense (by the network security system 120) and thus has increased its risk of receiving malicious code. Further, by physically bringing the mobile device 110 back into the trusted enterprise 140 and reconnecting from within, the mobile device 110 risks transferring any malicious code received to the intranet 115.

As the number of mobile devices and the number of attacks grow, mobile security is becoming increasingly important. The problem was emphasized in the recent Info-Security Conference in New York on Dec. 7-8, 2005. However, no complete solutions were presented.

Similarly, when a host device is connected to an external device such as a USB flash drive, iPod, external hard drive, etc., both devices are vulnerable to receipt of malicious code or transfer of private data. FIG. 11 illustrates an example prior art data exchange system 1100 that includes a host computer (host) 1105 and an external device 1110. The host 1105 includes a external device (ED) port 1115, such as a USB port, for receiving the external device 1110. The host 1105 also includes ED drivers 1120 for performing enumeration and enabling communications between the external device 1110 and the host 1105. The external device 1110 includes an ED plug, such as a USB plug, for communicating with the ED port 1115. Both of the host 1105 and external device 1110 are vulnerable to receipt of malicious code or transfer of private data.

SUMMARY

In various embodiments, a method comprises detecting a removable media device coupled to a digital device, authenticating a password to access the removable media device, injecting redirection code into the digital device, intercepting, with the redirection code, a request for data, determining to allow the request for data based on a security policy, and providing the data based on the determination. The method may further comprise selecting the security policy from a plurality of security policies based, at least in part, on the password and/or filtering the content of the requested data. Filtering the content may comprise scanning the data for malware. Filtering the content may also comprise scanning the data for confidential information.

Injecting redirection code into the digital device may comprise temporarily replacing one or more dlls within the digital device. Further, injecting redirection code into the digital device may comprise enumerating user processes of the digital device and injecting dlls to the enumerated user processes.

In some embodiments, the method further comprises receiving a shut down command and removing the redirection code in response to the shut down command. The method may also comprising removing the redirection code in response to a detection that the removable media device is no longer coupled to the digital device.

In various embodiments, the method further comprises intercepting, with the redirection code, a request to store data to the removable media device and determining to allow the request to store data based on the security policy.

An exemplary system may comprise an operating system, a login module, and a redirection module. The operating system may be configured to detect a removable media device coupled to a digital device. The login module may be configured to authenticate a password to access the removable media device and inject redirection code into the digital device. The redirection module may be configured to intercept a request for data, determine to allow the request for data based on a security policy, and provide the data based on the determination.

An exemplary computer readable media may comprise instructions. The instructions may be executable by a processor to perform a method. The method may comprise detecting a removable media device coupled to a digital device, authenticating a password to access the removable media device, injecting redirection code into the digital device, intercepting, with the redirection code, a request for data, determining to allow the request for data based on a security policy, and providing the data based on the determination.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a prior art network system in a first state.

FIG. 2 is a block diagram of a prior art network system in a second state.

FIG. 3 is a block diagram of a network system in accordance with an embodiment of the present invention.

FIG. 4 is a block diagram illustrating details of a computer system in accordance with an embodiment of the present invention.

FIGS. 5 and 5A are block diagrams illustrating details of the mobile security system in accordance with an embodiment of the present invention.

FIG. 6 is a block diagram illustrating details of the mobile security system in accordance with a Microsoft Window's embodiment.

FIG. 7 is a block diagram illustrating details of a smart policy updating system in accordance with an embodiment of the present invention.

FIG. 8 is a block diagram illustrating details of network security measures relative to the OSI layers.

FIG. 9 is a block diagram illustrating details of the communication technique for spreading security code to the mobile security systems.

FIGS. 10A-10C are block diagrams illustrating various architectures for connecting a mobile device to a mobile security system, in accordance with various embodiments of the present invention.

FIG. 11 is a block diagram illustrating a prior art data exchange system.

FIG. 12 is a block diagram illustrating a secure data exchange system, in accordance with an embodiment of the present invention.

FIG. 13 is a block diagram illustrating details of a security device, in accordance with an embodiment of the present invention.

FIG. 14 is a block diagram illustrating details of a security system, in accordance with an embodiment of the present invention.

FIG. 15 is a block diagram illustrating a secure data exchange system, in accordance with another embodiment of the present invention.

FIG. 16 is a flowchart illustrating a method of secure data exchange between a host and an external device, in accordance with an embodiment of the present invention.

FIG. 17 is a block diagram depicting a personal computer (PC) with a non-secured USB flash drive in the prior art.

FIG. 18 is a block diagram depicting a personal computer (PC) with a secured USB flash drive in the prior art.

FIG. 19 is a block diagram depicting a digital device and a removable media device in an embodiment.

FIG. 20 is a block diagram of the redirection module in an embodiment.

FIG. 21 is a data flow diagram in an embodiment.

FIG. 22 is a flow diagram of data flow of code injection in an embodiment.

FIG. 23 is a flow diagram of a method for dll injection in an embodiment.

FIG. 24 is a block diagram of an exemplary digital device.

DETAILED DESCRIPTION

The following description is provided to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the embodiments may be possible to those skilled in the art, and the generic principles defined herein may be applied to these and other embodiments and applications without departing from the spirit and scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles, features and teachings disclosed herein.

An embodiment of the present invention uses a small piece of hardware that connects to a mobile device and filters out attacks and malicious code. The piece of hardware may be referred to as a “mobile security system” or “personal security appliance.” Using the mobile security system, a mobile device can be protected by greater security and possibly by the same level of security offered by its associated corporation/enterprise.

FIG. 3 illustrates a network system 300 in accordance with an embodiment of the present invention. Network system 300 includes a desktop 305, a first mobile device 310 a, and a second mobile device 310 b. The first mobile device 310 a is illustrated as within the enterprise network 340 at this time and is coupled via a mobile security system 345 a to the enterprise's intranet 315. The desktop 305 and second mobile device 310 b are also within the enterprise network 340 but in this embodiment are coupled to the intranet 315 without an intervening mobile security system 345 such as mobile security system 345 b. The intranet 315 is coupled via a network security system 320 (which may be part of the enterprise's gateway) to the untrusted internet 330. Accordingly, the first mobile device 310 a, the second mobile device 310 b and the desktop 305 access the untrusted internet 330 via the network security system 320. Each may also be protected by a personal security system resident thereon (not shown). A third mobile device 310 c is currently outside the enterprise network 340 and is coupled via a mobile security system 345 b to the untrusted internet 330. The third mobile device 310 may be in use by an employee of the trusted enterprise 340 who is currently on travel. A security administrator 325 manages the mobile security system 345 a, the mobile security system 345 b, and the network security system 320 to assure that they include the most current security protection. One skilled in the art will recognize that the same security administrator need not manage the various devices. Further, the security administrator could be the user and need not be within the trusted enterprise 340.

Demarcation 335 divides the trusted enterprise 340 and the untrusted publicly accessible internet 330. Each of mobile device 310 a, 310 b and 310 c may be referred to generically as mobile device 310, although they need not be identical. Each mobile security system 345 a and 345 b may be referred to generically as mobile security system 345, although they need not be identical.

As shown, although the mobile device 310 c has traveled outside the trusted enterprise 340, the mobile device 310 c connects to the untrusted internet 330 via the mobile security system 345 b and thus retains two lines of defense (namely, the mobile security system 345 b and the security software resident on the device itself). In this embodiment, the mobile security system 345 effectively acts as a mobile internet gateway on behalf of the mobile device 310 c. In an embodiment, the mobile security system 345 may be a device dedicated to network security. In an embodiment, each mobile security system 345 may support multiple mobile devices 310, and possibly only registered mobile devices 310, e.g., those belonging to enterprise 340.

Each mobile security system 345 (e.g., 345 a, 345 b) may be a miniature server, based on commercial hardware (with Intel's Xscale as the core), Linux OS and network services, and open-source firewall, IDS/IPS and antivirus protection. The mobile security system 345 may be based on a hardened embedded Linux 2.6.

In this embodiment, because the security administrator 325 is capable of remotely communicating with the mobile security system 345 b, IT can monitor and/or update the security policies/data/engines implemented on the mobile security system 345 b. The security administrator 325 can centrally manage all enterprise devices, remotely or directly. Further, the security administrator 325 and mobile security systems 345 can interact to automatically translate enterprise security policies into mobile security policies and configure mobile security systems 345 accordingly. Because the mobile security system 345 may be generated from the relevant security policies of the enterprise 340, the mobile device 310 c currently traveling may have the same level of protection as the devices 305/310 within the trusted enterprise 340.

The mobile security system 345 may be designed as an add-on to existing software security or to replace all security hardware and software on a traveling mobile device. These security applications will preferably operate on different OSI layers to provide maximum security and malicious code detection, as shown in the example system illustrated in FIG. 8. Operating on the lower OSI layers and doing TCP/IP packets analysis only (by screening firewall or router packets) would miss virus and/or worm behavior. Also, many modern viruses use mobile code implemented on a “higher” level than the 7^(th) OSI layer (Application—HTTP, FTP, etc.) and therefore cannot be interpreted at the packet layer or at the application layer. For example, applying antivirus analysis only at the session or transport layer on a malicious Java Script (that is included in an HTML page), trying to match the signature with packets and without understanding the content type (Java Script), will not detect the malicious nature of the Java Script. To offer greater protection, the mobile security system 345 may act as corporate class security appliance and engage different security applications based on the content type and the appropriate OSI layers, (or even a “higher” level if content is encapsulated in the application layer). The mobile security system 345 may be configured to perform content analysis at different OSI layers, e.g., from the packet level to the application level. It will be appreciated that performing deep inspection at the application level is critical to detect malicious content behavior and improve detection of viruses, worms, spyware, Trojan horses, etc. The following software packages may be implemented on the mobile security system 345:

-   -   Firewall and VPN—including stateful and stateless firewalls,         NAT, packet filtering and manipulation, DOS/DDOS, netfilter,         isolate user mobile devices from the internet and run VPN         program on the device, etc.     -   Optional web accelerator and bandwidth/cache management based on         Squid.     -   IDS/IPS—Intrusion detection and prevention system based on         Snort. Snort is an open source network intrusion prevention and         detection system utilizing a rule-driven language, which         combines the benefits of signature, protocol- and anomaly-based         inspections.     -   Antivirus and antispyware based on ClamAV; additional AV and AS         engines, e.g., McAfee, Kaspersky, Pandamay, may be offered for         additional subscription fees.     -   Malicious Content Detection—on the fly heuristics that perform         content analysis to detect malicious content before having         signatures. This will be based on a rule base and updated rules         and will be content dependent scanning.     -   URL Categorization Filtering—based on a commercial engine, such         as Surfcontrol, Smart Filters or Websense. May provide around 70         categories of URLs such as gambling, adult content, news,         webmail, etc. The mobile device 345 may apply different security         policies based on the URL category, e.g., higher restriction and         heuristics for Gambling or Adult content web sites, etc.

FIG. 4 is a block diagram illustrating details of an example computer system 400, of which each desktop 305, mobile device 310, network security system 320, mobile security system 345, and security administrator 325 may be an instance. Computer system 400 includes a processor 405, such as an Intel Pentium® microprocessor or a Motorola Power PC® microprocessor, coupled to a communications channel 410. The computer system 400 further includes an input device 415 such as a keyboard or mouse, an output device 420 such as a cathode ray tube display, a communications device 425, a data storage device 430 such as a magnetic disk, and memory 435 such as Random-Access Memory (RAM), each coupled to the communications channel 410. The communications interface 425 may be coupled directly or via a mobile security system 345 to a network such as the internet. One skilled in the art will recognize that, although the data storage device 430 and memory 435 are illustrated as different units, the data storage device 430 and memory 435 can be parts of the same unit, distributed units, virtual memory, etc.

The data storage device 430 and/or memory 435 may store an operating system 440 such as the Microsoft Windows XP, the IBM OS/2 operating system, the MAC OS, UNIX OS, LINUX OS and/or other programs 445. It will be appreciated that a preferred embodiment may also be implemented on platforms and operating systems other than those mentioned. An embodiment may be written using JAVA, C, and/or C++ language, or other programming languages, possibly using object oriented programming methodology.

One skilled in the art will recognize that the computer system 400 may also include additional information, such as network connections, additional memory, additional processors, LANs, input/output lines for transferring information across a hardware channel, the internet or an intranet, etc. One skilled in the art will also recognize that the programs and data may be received by and stored in the system in alternative ways. For example, a computer-readable storage medium (CRSM) reader 450 such as a magnetic disk drive, hard disk drive, magneto-optical reader, CPU, etc. may be coupled to the communications bus 410 for reading a computer-readable storage medium (CRSM) 455 such as a magnetic disk, a hard disk, a magneto-optical disk, RAM, etc. Accordingly, the computer system 400 may receive programs and/or data via the CRSM reader 450. Further, it will be appreciated that the term “memory” herein is intended to cover all data storage media whether permanent or temporary.

FIG. 5 is a block diagram illustrating details of the mobile security system 345 in accordance with an embodiment of the present invention. Mobile security system 345 includes adapters/ports/drivers 505, memory 510, a processor 515, a preboot flash/ROM memory module 520 storing a secure version of the mobile security system's operating system and other applications, network connection module 525, security engines 530, security policies 535, security data 540, remote management module 550, distribution module 555, and backup module 560. Although these modules are illustrated as within the mobile security system 345, one skilled in the art will recognize that many of them could be located elsewhere, e.g., on the security administrator 325 or on third-party systems in communication with the mobile security system 345. The mobile security system 345 may be in a pocket-size, handheld-size or key-chain size housing, or possibly smaller. Further, the mobile security system 345 may be incorporated within the mobile device 310.

The adapters/ports/drivers 505 include connection mechanisms (including software, e.g., drivers) for USB, Ethernet, WiFi, WiMAX, GSM, CDMA, BlueTooth, PCMCIA and/or other connection data ports on the mobile security system 345. In one embodiment, the adapters/ports/drivers 505 may be capable of connection to multiple devices 310 to provide network security to the multiple devices 310.

Memory 510 and processor 515 execute the operating system and applications on the mobile security system 345. In this example, the preboot flash 520 stores the operating system and applications. At boot time, the operating system and applications are loaded from the preboot flash 520 into memory 510 for execution. Since the operating system and applications are stored in the preboot flash 520, which cannot be accessed during runtime by the user, the operating system and applications in the preboot flash 520 are not corruptible. Should the copy of the operating system and applications in memory 510 be corrupted, e.g., by malicious code, the operating system and applications may be reloaded into the memory 510 from the preboot flash 520, e.g., upon restart. Although described as stored within the preboot flash 520, the OS and applications can be securely stored within other read-only memory devices, such as ROM, PROM, EEPROM, etc.

As shown in FIG. 5A, memory (including memory 510 and preboot flash 520) on the mobile security system 345 may be divided into the following zones: read only memory 570; random access memory 575 for storing a copy of the OS, kernel and security applications; runtime environment 580; and database 585 for storing application data, log files, etc. Upon each “hard” restart, the boot loader (resident in read only memory 570) of the mobile security system 345 copies the kernel and security applications (a fresh unchanged copy) from read only memory 570 to random access memory 575. This causes a clean version of the OS and applications to be loaded into random access memory 575 each time. That way, if a special attack on mobile security system 345 is developed, the attack will be unable to infect the system, since the OS and applications are precluded from accessing read only memory 570 during runtime. Further, any attack that does reach memory 510 will be able to run only once and will disappear upon a hard restart. A triggering mechanism may be available to restart the mobile security system 345 automatically upon infection detection.

The network connection module 525 enables network connection, e.g., to the internet 330 or the intranet 315 via network communication hardware/software including WiFi, WiMAX, CDMA, GSM, GPRS, Ethernet, modem, etc. For example, if the mobile device 310 wishes to connect to the internet 330 via a WiFi connection, the adapters/ports/drivers 505 may be connected to the PCI port, USB port or PCMCIA port of the mobile device 310, and the network connection module 525 of the mobile security system 345 may include a WiFi network interface card for connecting to wireless access points. Using the network connection module 425, the mobile security system 345 may communicate with the network as a secure gateway for the mobile device 310. Other connection architectures are described in FIGS. 10A-10C.

The security engines 530 execute security programs based on the security policies 535 and on security data 540, both of which may be developed by IT managers. Security engines 530 may include firewalls, VPN, IPS/IDS, antivirus, antispyware, malicious content filtering, multilayered security monitors, Java and bytecode monitors, etc. Each security engine 530 may have dedicated security policies 535 and security data 540 to indicate which procedures, content, URLs, system calls, etc. the engines 530 may or may not allow. The security engines 530, security policies 535 and security data 540 may be the same as, a subset of, and/or developed from the engines, policies and data on the network security system 320.

To provide a higher security level provided by antivirus and antispyware software, the security engines 530 on each mobile security system 345 may implement content analysis and risk assessment algorithms. Operating for example at OSI Layer 7 and above (mobile code encapsulated within Layer 7), these algorithms may be executed by dedicated High Risk Content Filtering (HRCF) that can be controlled by a rules engine and rule updates. The HRCF will be based on a powerful detection library that can perform deep content analysis to verify real content types. This is because many attacks are hidden within wrong mime types and/or may use sophisticated tricks to present a text file type to a dangerous active script or ActiveX content type. The HRCF may integrate with a URL categorization security engine 530 for automatic rule adjustment based on the URL category. In one embodiment, when the risk level increases (using the described mechanism) the mobile security system 345 may automatically adjust and increase filtering to remove more active content from the traffic. For example, if greater risk is determined, every piece of mobile code, e.g., Java script, VB script, etc. may be stripped out.

Three aspects for integration with corporate policy server legacy systems include rules, LDAP and active directory, and logging and reporting as discussed below. In one embodiment, a policy import agent running on the security administrator 325 will access the rule base of Checkpoint Firewall-1 and Cisco PIX Firewalls and import them into a local copy. A rule analysis module will process the important rules and will offer out-of-the-box rules and policies for mobile security systems 345. This proposed policy will offer all mobile security systems 345 a best fit of rules that conform the firewall policy of the enterprise 340. The agent will run periodically to reflect any changes and generate updates for mobile security system 345 policies 535. The LDAP and Active Directory may be integrated with the directory service to maintain mobile security system 345 security policies 535 that respond to the enterprise's directory definitions. For example, a corporate policy for LDAP user Group “G” may automatically propagate to all mobile security systems 345 in “G” group. Mobile security system 345 local logs and audit trails may be sent in accordance to a logging and reporting policy to a central log stored at the security administrator 325. Using a web interface, IT may be able to generate reports and audit views related to all mobile device 310 users, their internet experiences, and attempts to bring infected devices back to the enterprise 340. IT will be able to forward events and log records into legacy management systems via SYSLOG and SNMP Traps.

The security engines 530 may perform weighted risk analysis. For example, the security engine 530 may analyze HTTP, FTP, SMTP, POP3, IM, P2P, etc. including any traffic arriving from the internet 330. The security engine 530 may assign a weight and rank for every object based on its type, complexity, richness in abilities, source of the object, etc. The security engine 530 may assign weight based on the source using a list of known dangerous or known safe sources. The security engine 530 may assign weight to objects based on the category of the source, e.g., a gambling source, an adult content source, a news source, a reputable company source, a banking source, etc. The security engine 530 may calculate the weight, and based on the result determine whether to allow or disallow access to the content, the script to run, the system modification to occur, etc. The security engine 530 may “learn” user content (by analyzing for a predetermined period of time the general content that the user accesses) and accordingly may create personal content profiles. The personal content profile may be used to calibrate the weight assigned to content during runtime analysis to improve accuracy and tailor weighted risk analysis for specific user characteristics.

In some embodiments, the security engines 530, security policies 535 and security data 540 may enable bypassing the mobile security system 345. The security policy 535, set by the security administrator 325, may include a special attribute to force network connection through the mobile security system 325 when outside the trusted enterprise 340. Thus, if this attribute is set “on,” when a mobile device 310 attempts to connect to the internet 330 without the mobile security system 345 and not from within the trusted enterprise 340, all data transfer connections including LAN connection, USB-net, modem, Bluetooth, WiFi, etc. may be closed. The mobile device 310 may be totally isolated and unable to connect to any network, including the internet 330.

In one embodiment, to enable this, when first connecting the mobile security system 345 to the mobile device 310 using for example the USB cable (for both power and USB connection creation), the USB plug & play device driver will be sent into the mobile device 310. The installed driver may be “Linux.inf” which allows a USB-net connection for the mobile security system 345. This connection allows the mobile security system 345 to access the internet 330 via the USB port and using the mobile device 310 network connection plus additional code (“the connection client”). In a Windows example, the connection client may be installed at the NDIS level of the mobile device 310 above all the network interface cards of every network connection as shown in FIG. 6. The implementation will be as an NDIS Intermediate (IM) Driver or NDIS-Hooking Filter Driver. Both implementations may be at the kernel level, so that an end user cannot stop or remove it. When starting the mobile device 310, the connection client may attempt to connect to the security administrator 325 or the network security system 320 locally within the trusted enterprise 340. If the node is not found (finding via VPN is considered as not found in local LAN), the connection client will assume it is working from outside the trusted enterprise 340 and expects to find the mobile security system 345 connected, e.g., via USB-net or other connection mechanism. If the mobile security system 345 is not found, the connection client may avoid any communication to any network connection. By a policy definition, this behavior can be modified to allow communication to the enterprise 340 via VPN installed in the mobile device 310. Similarly, in case of a mobile device system 345 failure, all traffic may be disabled, except for the VPN connection into the enterprise 340.

It will be appreciated that NDIS is one possible implementation of intercepting traffic at the kernel level. For example, in another embodiment, the system may hook Winsock or apply other ways that may be in future Windows versions.

In an embodiment where the mobile security system 345 supports multiple mobile devices 310, the security engines 530, security policies 535 and security data 540 may be different for each mobile device 310 (e.g., based on for example user preferences or IT decision). Alternatively, it can apply the same engines 530, policies 535 and data 540 for all connected devices 310.

The remote management module 550 enables communication with security administrator 325 (and/or other security administrators), and enables local updating of security engines 530, security policies 535, security data 540 including signatures and other applications. In one embodiment, modification to the security policies 535 and data 540 can be done by the security administrator 325 only. The remote management module 550 of the mobile security system 345 may receive updates from an update authorities device (UAD), e.g., on the security administrator 325 via a secured connection. A UAD may operate on an update server at a customer IT center located on the internet 330 to forward updates to mobile security systems 345 that possibly do not belong to an enterprise 540 in charge of managing updates. A UAD may operate on a mobile security system 345. Security engine 530 updates may modify the antivirus engine DLL, etc. OS and security application updates may be implemented only from within the enterprise 540 while connecting to the security administrator 325 and via an encrypted and authenticated connection.

The security administrator 325 can modify URL black and white lists for remote support to traveling users. In case of false positives, the security administrator 325 may allow access to certain URLs, by bypassing the proactive heuristics security but still monitoring by firewall, antivirus, IPS/IDS, etc. Additional remote device-management features may enable the security administrator 325 to perform remote diagnostics, access local logs, change configuration parameters, etc. on the mobile security system 345. The security administrator 325 may delegate tasks to a helpdesk for support.

The remote management module 550 may communicate with a wizard (e.g., wizard 745), which may be on the security administrator 325, as illustrated in FIG. 7, or on another system. Details of the wizard 745 and details of the communication schemes between the remote management module 550 and the wizard 745 are described below with reference to FIG. 7.

The distribution module 555 enables distribution of updates, e.g., security policy 535 updates including rule updates, security data 540 updates including signature updates, security engine 530 updates, application/OS updates, etc. by the mobile security system 345 to N other mobile security systems 345. A routing table identifying the N other mobile security systems 345 to whom to forward the updates may be provided to the distribution module 555 to enable system 345 to system 345 communication. Updates may be implemented according to policies set by the security administrator 325. When forwarding updates, the distribution module 555 acts as a UAD.

Each mobile security system 345 may obtain its routing table with security information updates, periodically, at predetermined times, upon login, etc. The routing tables may be maintained on a server, e.g., the security administrator 325 or another mobile security system 345. In one embodiment, the mobile security systems 345 may contact the server to retrieve the routing tables. Alternatively, the server may push the routing tables to the mobile security systems 345.

The distribution module 555 may enable rapid updates as shown in FIG. 9. Currently, all commercial antivirus products available do not update devices faster than viruses spread. To assure that a new virus attack does not spread faster than for example signature updates, each mobile security system 345 may be an active UAD. In one embodiment, as shown in FIG. 9, each mobile security system 345 is responsible for forwarding the signature updates to four other devices 345. As one skilled in the art will recognize, all devices 345 need to forward to the same number of other devices 345. Multiple devices 345 may be responsible for forwarding to the same device 345. When necessary, offline devices 345 being activated may poll the server, e.g., the security administrator 325, for routing table updates. Many other updating techniques are also possible.

The backup module 560 may constantly backup image and changes of the boot sector and system files of the mobile device 310 into the flash memory 520 or into another persistent memory device. That way, in case of major failure, including a loss of the system or boot sector of the mobile device 310, the mobile security system 345 may be identified as a CD-ROM during reboot and may launch the backup module (or separate program) to restore the boot sector and system files on the mobile device 310, thereby recovering the mobile device 310 without the need for IT support. In an embodiment where the network security system 345 supports multiple mobile devices 310, the backup module 560 may contain separate boot sector and system files for each of the mobile devices 310, if different.

FIG. 7 is a block diagram illustrating details of a smart policy updating system 700 in accordance with an embodiment of the present invention. System 700 includes the security administrator 325 coupled to the network security system 320 and to the mobile security system 345. The network security system 320 includes security engines 705, including an antivirus engine 715, an IPS/IDS engine 720, a firewall engine 725, and other security engines. The network security system 320 also includes security policies and data 710, including antivirus policies and data 730, IPS/IDS policies and data 735, firewall policies and data 740, and other policies and data. Similarly, the mobile security system 345 includes an antivirus engine 755, an IPS/IDS engine 760, a firewall engine 765, and other engines. The mobile security system 345 also includes security policies and data 535/540, including antivirus security policies and data 770, IPS/IDS security policies and data 775, firewall security policies and data 780, and other security policies and data.

The security administrator 325 includes a wizard 745 for enabling substantially automatic initial and possibly dynamic setup of the security engines 530, security policies 535 and security data 540 on the mobile security system 345. In one embodiment, the wizard 745 may automatically load all security engines 705 and policies and data 710 of the network security system 320 as the security engines 530 and policies and data 535/540 on the mobile security system 345. In another embodiment, the wizard 745 may include all security engines 705 and policies and data 710 except those known to be irrelevant, e.g., those related to billing software used by accounting, those relating to web software running only on the web servers, etc. In another embodiment, the engines 530 would need to be loaded by an IT manager, and would not be loaded automatically by the wizard 745.

In one embodiment, the wizard 745 may determine whether the mobile security system 345 requires a particular security engine 530, e.g., an antivirus engine 755, IPS/IDS engine 760, firewall engine 765, etc. If so determined, then the wizard 745 would load the engine 530 onto the mobile security system 345. The wizard 745 would then determine which policies and data sets, e.g., some for antivirus engine 755, some for the IPS/IDS engine 760, some for the firewall engine 765, etc. are important to the mobile security system 345. The wizard 745 will then determine which of the antivirus policies and data 730 on the network security system 320 are relevant to the antivirus policies and data 770 on the mobile security system 345, which of the IPS/IDS policies and data 735 on the network security system 320 are relevant to the IPS/IDS policies and data 775 on the mobile security system 345, which of the firewall policies and data 740 on the network security system 320 are relevant to the firewall policies and data 780 on the mobile security system 345, and which of the other policies and data on the network security system 320 are relevant to the policies and data on the mobile security system 345. As stated above, the wizard 745 may determine that all security engines 705 or just a subset are needed on the mobile security system 345. The wizard 745 may determine that all policies and data 710 for a given engine type or just a subset should be forwarded. The wizard 745 may determine which relevant policies and data 710 should be forwarded to the mobile security system 345 based on rules developed by an IT manager, based on item-by-item selection during the setup procedure, etc. Alternative to the wizard 745, an IT manager can setup the engines 530 and policies and data 535/540 on the mobile security system 345 without the wizard 745.

The security administrator 325 may also include an update authorities device 750. The update authorities device 750 may obtain security system updates (e.g., signature updates) and may send the updates to the network security system 320 and to the mobile security system 345. One skilled in the art will recognize that the updates to the network security system 320 and the updates to the mobile security system 345 need not be the same. Further, the update authorities device 750 may obtain the updates from security managers, security engine developers, antivirus specialists, etc. The update authorities device 750 may forward the updates to all network security systems 320 and all mobile security systems 345, or may forward routing tables to all mobile security systems 345 and the updates only to an initial set of mobile security systems 345. The initial set of mobile security systems 345 may forward the updates to the mobile security systems 345 identified in the routing tables in a P2P manner, similar to the process illustrated in FIG. 9. As stated above, each mobile security system 345 operating to forward updates is itself acting as an update authorities device 750.

Other applications may be included on the mobile security system 345. For example, add-on applications for recurring revenue from existing customers may include general email, anti-spam, direct and secured email delivery, information vaults, safe skype and other instant messaging services, etc.

-   -   Email Security and Anti-spam—implementation of mail relay on         mobile security systems 345 (including the web security engine         above) and a local spam quarantine (based on SendMail or similar         process) may implement a complete mail security suite (SMTP and         POP3) including anti-spam with real time indexing (via online         web spam quarries). Users may have access to the quarantine to         review spam messages, release messages, modify and custom spam         rules, etc., via a web interface.     -   Direct and Secured Email Delivery based on mail relay will allow         the mobile security system 345 to send user email directly from         one mobile security system 345 to another mobile security system         345 without using in route mail servers. This allows corporate         users to send emails that need not travel in the internet, thus         leaving trace and duplicates on different unknown mail servers         in route. This combined with the ability to use a secured pipe         between two mobile security systems is valuable to corporations.         Without such methodology, people could trace emails exchange         without accessing to the enterprise's mail server, by tracking         down copies in intermediate mail servers that were used to         deliver the messages.     -   Information Vault—Application to encrypt and store end user         information on the mobile security system 345 may be available         only to authorized users via a web interface and a web server         implemented on every mobile security system 345 (e.g., BOA,         Apache, etc.)     -   Safe Skype and Other IM—implementing an instant messaging client         on the mobile security system 345 can guarantee that the instant         messaging system or P2P application has no access to data on the         mobile device 310. Adding a chipset of AC/97 to provide a sound         interface on the mobile security system 325 could allow users to         talk and receive calls directly from/to the mobile security         system 325.

Although not shown, a small battery may be included with the mobile security system 345. This battery may be charged by the USB connection during runtime or using the power adapter at any time. The battery may guarantee proper shutdown, e.g., when user disconnects the USB cable from the mobile security system 345. It will be signaled by the system which will launch applications and system shutdown. This will ensure a proper state of the file system and flashing open files buffers.

A multi-layered defense and detection abilities is required. This may be done by a special code that is constantly monitoring the scanning result by different systems (antivirus, IDS/IPS, firewall, antispyware, URL category, etc.) and at different levels to build a puzzle and identify an attack even if its not recognized by each of the individual subsystems. By doing this, the mobile security system 345 will maintain and in some cases even improve the security level provided within the enterprise 540.

One available benefit of the mobile security system 345 is its ability to enforce the policy of the enterprise 540 on the end user while they are traveling or working from home. Since the mobile security system 345 uses similar security engines and policy as when connected from within the enterprise 540 and since the end user cannot access the internet 330 without it (except via VPN connection into the enterprise 540), IT may be capable of enforcing its security policy beyond the boundaries of the enterprise 540. The OS may be under the entire supervision of IT, while the mobile security system 345 OS acts as an end user OS under his control. This resolves the problems of who controls what and how security and productivity face minimal compromise.

A standalone version of the mobile security system 345 may offer the same functionality, and may provide a local management interface via web browser. Attractive to home users and small offices that lack an IT department, the mobile security system 345 enables the end user to launch a browser, connect to the mobile security system 345, set the different policies (update policy, security rules, etc.) including modifying the white and black URL lists, etc. There is also an opportunity to provide end users with a service of remote management of the mobile security systems 345 by subscription.

FIGS. 10A, 10B and 10C illustrate three example architectures of connecting a mobile security system 345 to a mobile device 310, in accordance with various embodiments of the present invention. In FIG. 10A, the mobile device 310 is coupled to the mobile security system 345 via USB connections 1015 and 1020 and is coupled to the internet 330 via a NIC card 1005. The mobile device 310 receives internet traffic from the internet 330 via its NIC card 1005. A kernel-level redirector 1010 (e.g., via NDIS, Winsock, etc.) on the mobile device 310 automatically redirects the internet traffic via the USB connections 1015 and 1020 to the mobile security system 345, which scans, cleans and returns the cleaned internet traffic to the mobile device 310 via the USB connections 1015 and 1020. In FIG. 10B, the mobile device 310 is coupled to the mobile security system 345 via USB connections 1025 and 1030. The mobile security system 345 includes a NIC card 1035 for receiving internet traffic from the internet 330. The mobile security system 345 scans, cleans and forwards the internet traffic via the USB connections 1025 and 1030 to the mobile device 310. In FIG. 10C, the mobile device 310 is coupled to the mobile security system 345 via NIC cards 1040 and 1045. The mobile security system 345 receives internet traffic from the internet 330 via its NIC card 1045. The mobile security system 345 scans, cleans and forwards the internet traffic wirelessly via the NIC cards 1040 and 1045 to the mobile device 310. Other connection architectures are also possible.

FIG. 12 is a block diagram illustrating a secure data exchange system 1200, in accordance with an embodiment of the present invention. The secure data exchange system 1200 includes a host computer (host) 1205 coupled via a security device 1210 to an external device 1110. The host 1205 may include a laptop, desktop, PDA, mobile phone, or other processor-based device. The external device 1110 may be any external device with memory such as a USB drive, external hard drive, PDA, music player, cell phone, etc. The security device 1210 is communicatively coupled to the host 1205 via an ED port 1225 (USB, serial, parallel, Firewire, Ethernet, WiFi, WiMAX, GSM, CDMA, BlueTooth, PCMCIA and/or other connection) and an ED plug 1230 (USB, serial, parallel, Firewire, Ethernet, WiFi, WiMAX, GSM, CDMA, BlueTooth, PCMCIA and/or other connection). The external device 1110 is communicatively coupled to the security device 1210 via an ED port 1235 (USB, serial, parallel, Firewire, Ethernet, WiFi, WiMAX, GSM, CDMA, BlueTooth, PCMCIA and/or other connection) and ED plug 1120 (USB, serial, parallel, Firewire, Ethernet, WiFi, WiMAX, GSM, CDMA, BlueTooth, PCMCIA and/or other connection). The connector type of the ED port 1225 and ED plug 1230 combination may be different that the connector type of the ED port 1235 and ED plug 1120 combination. In one embodiment, all ports 1225/1235 and plugs 1230/1120 are USB. Although the plugs 1120/1230 are illustrated as male and ports 1225/1235 are shown as female, one skilled in the art will recognize that the opposite is possible (plugs 1120/1230 may be female and ports 1225/1235 may be male).

The host 1205 includes ED drivers 1220 for performing enumeration and enabling communication with the security device 1210. Similarly, the security device 1210 includes ED drivers 1245 for performing enumeration and enabling communication with the external device 1110.

In one embodiment, the security device 1210 includes a programmable hardware appliance capable of enforcing security policies to protect against malicious code such as viruses, spyware, adware, Trojan Horses, etc. and to protect against transfer of private data. In one embodiment, the security device 1210 is configured to protect both the host 1205 and the external device 1215. In one embodiment, the security device 1210 is configured to protect only one of the external device 1110 or the host 1205. Additional details of the security device 1210 are provided with reference to FIGS. 13 and 14.

FIG. 13 is a block diagram illustrating details of the security device 1210, in accordance with an embodiment of the present invention. The security device 1210 includes a processor 1305, such as an Intel Pentium® microprocessor or a Motorola Power PC® microprocessor, coupled to a communications channel 1315. The security device 1210 further includes an ED plug 1230, an ED port 1235, a communications interface 1310, storage 1320 such as an EEPROM, and memory 1325 such as Random-Access Memory (RAM) or Read Only Memory (ROM), each coupled to the communications channel 1315. The communications interface 1310 may be coupled to a network such as the internet. One skilled in the art will recognize that, although the storage 1320 and memory 1325 are illustrated as different units, the data storage device 1320 and memory 1325 can be parts of the same unit, distributed units, virtual memory, etc. The term “memory” herein is intended to cover all data storage media whether permanent or temporary. One skilled in the art will recognize that the security device 1210 may include additional components, such as network connections, additional memory, additional processors, LANs, input/output lines for transferring information across a hardware channel, the internet or an intranet, etc.

As shown, memory 1325 stores an operating system 1330 such as the Microsoft Windows XP, the IBM OS/2 operating system, the MAC OS, Unix OS, Linux OS, etc. It will be appreciated that a preferred embodiment may also be implemented on platforms and operating systems other than those mentioned. An embodiment may be written using JAVA, C, and/or C++ language, or other programming languages, possibly using object oriented programming methodology. The memory 1325 also stores ED drivers 1245 and a security system 1335. The ED drivers 1245 may include standard drivers for standard external devices 1110 and proprietary drivers for proprietary external devices 1110. The ED drivers 1245 may be transferred onto the memory 1325 via ED plug 1230. The security system 1335 includes code for enforcing security policies on data transfer actions between the host 1205 and external device 1110.

FIG. 14 is a block diagram illustrating details of a security system 1335, in accordance with an embodiment of the present invention. The security system 1335 includes a security manager 1405, security engines 1410, security policies 1415, and security data 1420.

In one embodiment, the security manager 1405 includes code for performing enumeration, namely, to identify the external device 1110 or external device 1110 type and to identify the corresponding ED driver 1245 capable of establishing communication between the security device 1210 and the external device 1110. The security manager 1405 also includes code to control execution of the various security engines 1410 based on the security policies 1415 and security data 1420 to evaluate data transfer requests or other device requests. Further, the security manager 1405 includes code to communicate with the host 1205, which will be the source of the data transfer and/or other requests.

In one embodiment, the security engines 1410 includes code for securing the transfer of data between the host 1205 and the external device 1110 based on the security policies 1415 and security data 1420. The security engines 1410 may include firewalls, antivirus, antispyware, malicious content filtering, multilayered security monitors, Java and bytecode monitors, etc. The security engines 1410 may also include data privacy modules to enforce data privacy policies 1415. Each security engine 1410 may have dedicated security policies 1415 and security data 1420 to indicate which procedures, URLs, system calls, content, ID, etc. the data requested for transfer may contain or whether the data requested for transfer is considered nontransferable (or nontransferable without additional security measure such as a password and ID).

To provide a higher security level, the security engines 1410 may implement content analysis and risk assessment algorithms. In one embodiment, a security engine 1410 assigns a weight and rank for every transfer object based on its type, complexity, richness in abilities, source, etc. The security engine 1410 may assign weight based on the source using a list of known dangerous or known safe sources. The security engine 1410 may assign weight to objects based on the category of the source, e.g., a gambling source, an adult content source, a news source, a reputable company source, a banking source, etc. The security engine 1410 may calculate the weight, and based on the result determine whether to allow or disallow access to the content, the script to run, the system modification to occur, etc. The security engine 1410 may “learn” user content (by analyzing for a predetermined period of time the general content that the user accesses) and accordingly may create personal content profiles. The personal content profile may be used to calibrate the weight assigned to content during runtime analysis to improve accuracy and tailor weighted risk analysis for specific user characteristics.

Thus, upon receiving a data transfer and/or other request from the host 1205, the security manager 1405 will launch the appropriate security engines 1410 based on the security policies 1415. For example, the security policies 1415 may be configured not to allow specific ActiveX controls to be loaded from the host 1205 onto the external device 1110. The security policies 1415 may be configured not to allow data transfer from private folders on the host 1205 to the external device 1110. The security manager 1405 will launch the appropriate security engines 1410 to assure that these example security policies 1415 are met. Further, the security engines 1410 may use security data 1420, which may include definition files of malicious ActiveX controls, locations of private folders, etc.

Although not shown, the security system 1335 may include additional components such as the preboot flash 520 with OS and applications, the remote management module 550, the distribution module 555, and the backup module 560 discussed above with reference to FIG. 5. Other components are also possible.

FIG. 15 is a block diagram illustrating a secure data exchange system 1500, in accordance with another embodiment of the present invention. The secure data exchange system 1500 includes a security device 1505 communicatively coupled to the host 1520 via an ED plug 1515 on the security device 1505 and a first ED port 1525 on the host 1520. The secure data exchange system 1500 also includes an external device 1110 communicatively coupled to the host 1520 via the ED plug 1120 on the external device 1110 and a second ED port 1535 on the host 1520.

Because the external device 1110 is not directly coupled to the security device 1505, the security device 1505 is not physically intercepting the data transfer requests between the external device 1110 and the host 1520. Accordingly, in this embodiment, the host 1520 includes a redirect driver 1530, which is configured to redirect data transfer requests between the external device 1110 and the host 1520 regardless of data transfer direction. In one embodiment, the security device 1505 may be configured to protect only one of the external device 1110 or the host 1520. Further, in one embodiment, the security device 1505 does not contain any ED drivers, e.g., ED drivers 1245.

In one embodiment, if the security device 1505 is not coupled to the host 1520, the host 1520 uses the ED drivers 1540 to communicate with the external device 1110. In one embodiment, the host 1520 is configured not to communicate with the external device 1110 until the security device 1505 is coupled to the host 1520. In one embodiment, the host 1520 uses the ED drivers 1540 to communicate with the external device 1110 only if additional security measures are taken, such as receipt of a password and ID, or until the security device 1505 is coupled to the host 1520.

In one embodiment, the host 1520 may conduct enumeration of the security device 1505 upon connection of the security device 1505 to the ED port 1525. Upon identifying the security device 1505 or security device 1505 type, the host 1520 may initiate the redirect driver 1530 to redirect all data transfer requests or other external device 1110 requests from all other ED ports 1535 to the security device 1505. In one embodiment, the redirect driver 1530 only accepts data transfer requests from the security device 1505, which presents the requests of the external device 1110 as a proxy. In one embodiment, the redirect driver 1530 performs data transfer requests received from the external device 1110 only after the security device 1505 has conducted its check and given its authorization. Other protocols are also possible.

FIG. 16 is a flowchart illustrating a method 1600 of secure data exchange between a host and an external device, in accordance with an embodiment of the present invention. The method 1600 begins in step 1605 with the security device 1505 being connected to the first ED port 1525 of the host 1520. The external device 1110 in step 1610 is connected to the second ED port 1535 of the host 1520. The host 1505 in step 1615 performs enumeration techniques to identify the security device 1505 and the external device 1110 and to install the appropriate drivers 1530/1540 to enable communication with the security device 1505 and the external device 1110. The redirect driver 1530 in step 1620 receives a data transfer request from either the host 1505 to the external device 1110 or from the external device 1110 to the host 1505. The redirect driver 1530 in step 1625 redirects the data transfer request to the security device 1505, which in step 1630 enforces its security policies (antivirus, antispyware, anti-adware, data privacy, etc.) on the data transfer request. The security device 1505 in step 1635 determines whether the data transfer request passes the security policies. If so, then the security device 1505 in step 1640 authorizes the data transfer request and the host 1520 in step 1645 performs the data transfer request. If not, then the security device 1505 in step 1650 rejects the data transfer request. Method 1600 then ends.

It will be appreciated that, in one embodiment, the security device 1210/1505 may be implemented as part of the host 1205/1520, e.g., within the housing of the host 1205/1520 and/or as a security procedure executed by the host 1205/1520.

FIG. 17 is a block diagram 1700 depicting a personal computer (PC) 1702 with a non-secured USB flash drive 1704 in the prior art. The personal computer 1702 includes a file system 1706 and an operating system 1708. The personal computer may be in communication with the hard drive 1710 and an application 1712. The non-secured USB flash drive 1704 includes a controller 1714 and flash memory 1716.

The personal computer 1702 may be any personal computer such as a laptop or desktop computer. The file system 1706 is software configured to organize files on the personal computer 1702. The operating system 1708 is any operating system (e.g., Microsoft Windows, Apple OS, Linux, or Unix) that controls the personal computer 1702.

The hard drive 1710 is any hard drive and may be contained within the personal computer 1702. In one example, the file system 1706 and the operating system 1708 may be stored on the hard drive 1710. The hard drive 1710 may be contained within a different personal computer 1702.

The application 1712 may be any application (e.g., word processing program or communication program) and may call for data on the non-secured USB flash drive 1704. The application 1712 may be executed by the personal computer 1702 or by a second personal computer (not depicted) that is in communication with the personal computer 1702.

The non-secured USB flash drive 1704 is any thumb drive that contains a controller 1714 and flash memory 1716. The controller 1714 is a flash controller. The non-secured USB flash drive 1704 does not contain security to prevent the flash memory 1716 from being accessed. For example, a password is not required to access the flash memory 1716. Further, the data within the flash memory 1716 is not encrypted.

In one example of the prior art, a user connects the non-secured USB flash drive 1704 to the personal computer 1702 via a USB interface. Once connected, the operating system 1706 may be configured to mount the non-secured USB flash drive 1704. The file system 1706 may then identify the flash memory 1716 within the non-secured USB flash drive 1704 as a removable drive. The application 1712 may access the data residing on the hard drive 1710 and the non-secured USB flash drive 1704 through the file system 1706 and/or the operating system 1708.

In the prior art, once the non-secured USB flash drive 1704 is mounted by the operating system 1708, full access to all of the data within the flash memory 1716 is allowed. Further, there is no content screening where data on the flash memory 1716 is checked for viruses or other malware before a user or an application (e.g., application 1712) is allowed access. There is also no real-time journaling or audit trail tracking access or changes to the flash memory 1716.

FIG. 18 is a block diagram 1800 depicting a personal computer (PC) 1802 with a secured USB flash drive 1804 in the prior art. The personal computer 1802 includes a file system 1806 and an operating system 1808 which may be in communication with a hard drive 1810. The personal computer 1802 may execute an application 1812. The secured USB flash drive 1804 includes a controller 1814 and flash memory 1816. The PC 1802, file system 1806, operating system 1808, hard drive 1810, and application 1812 may be similar to the PC 1702, file system 1706, operating system 1708, hard drive 1710, and application 1712 depicted in FIG. 17.

The secured USB flash drive 1804 is any thumb drive with at least some security that contains a controller 1814 and flash memory 1816. Unlike the non-secured USB flash drive 1704 (depicted in FIG. 17), the secured USB flash drive 1804 may require a password to access the flash memory 1816. The flash memory 1816 may also be encrypted.

In one example, once the secured USB flash drive 1804 is connected to the PC 1802, the secured USB flash drive 1804 may be represented by the file system 1806 as a CD drive with a “login.exe” 1818 executable application. The “login” application 1818 may be executed (e.g., by the user through the file system 1806 or automatically by the operating system 1808). Once the “login” application is executed, the user may be prompted for a password. If no password is entered or an incorrect password is received by the secured USB flash drive 1804, access to the flash memory 1816 may be denied. Upon entering a correct password, the controller 1814 may allow access to the data stored in the flash memory 1816 and/or decrypt data from the flash memory 1816.

Unfortunately, once the secured USB device 1804 is mounted by the operating system 1808, and a password is entered, full access to all of the data within the flash memory 1816 is allowed. In one example, every user or application that accesses the PC 1802 may be able to access all of the data within the secured USB flash drive 1804.

Further, even though the secured USB device 1804 requires limited security, there is no content screening where data on the flash memory 1816 is scanned for viruses immediately prior to delivery of the file. There is also a lack of file-based policies and, as a result, there is no granular access control at the file level. For example, once access to the flash memory 1816 is obtained, unlimited access is granted to the user. In the prior art, there is no rules or application that limit specific users or groups of users access to a limited number of files within the flash memory 1816 or provide different users with different applications based, at least in part, on different passwords. Further, there is also no real-time journaling or audit trail tracking access to or changes to the flash memory 1716. There is also no real-time journaling or audit trail tracking the user credentials of the accessing user.

FIG. 19 is a block diagram depicting a digital device 1902 and a removable media device 1904 in an embodiment. The digital device 1902 may comprise a file system 1906, an operating system 1908, and a redirection module 1910. The file system 1906, the operating system 1908, and redirection module 1910 may be in communication with the application 1912 and a hard drive 1914. The application 1912 may be executed by the digital device 1902 or on a second digital device (not depicted). The digital device 1902 may comprise the hard drive 1914 or, alternately, a second digital device may comprise the hard drive 1914. The removable media device 1904 may comprise the controller 1916, the flash memory 1918, and the login module 1920.

A digital device 1902 is any device with a processor and memory (e.g., personal computer). The digital device is described further herein. The removable media device 1904 is any removable device that comprises a computer readable media (e.g., media that may contain instructions that are executable by a processor of a computer). In some examples, the removable media device 1904 may comprise a USB flash drive, thumbdrive, removable hard drive, multimedia device (e.g., Apple Ipod, Apple Iphone, or Microsoft Zune), camera, or any other device with memory configured to be in communication with the digital device 1902.

The operating system 1908 may be any operating system such as, but not limited to, Microsoft Windows, Apple OS, Linux, Unix, or the like. The file system 1910 may be any file system configured to work with the operating system 1908.

The redirection module 1910 may be hardware, software, or a combination of hardware and software. The redirection module 1910 redirects (e.g., intercepts) commands, and/or function calls to and from the operating system 1908. The redirection module 1910 may also redirect processes. In some embodiments, functionality from the operating system 1908 and/or the file system 1906 is replaced by commands or instructions from the redirection module 1912. In various embodiments, the redirection module 1912 adds commands and new functionality that is to be performed in addition to the functionality from the operating system 1908 and/or the file system 1906.

In some embodiments, the redirection module 1910 comprises one or more dll(s) injected from the removable media device 1904. The injected dll(s) may temporarily replace existing dll(s) of the file system 1906 and/or operating system 1908. In one example, a user of the digital device 1902 attempts to open a file in the flash memory 1918 of the removable media device 1904. The open command calls one or more of the dll(s) of the redirection module 1910.

The dlls of the redirection module 1910 may replace functionality of the operating system 1908 or perform functions in addition to the functionality of the operating system 1908. In one example, the user attempts to open a file in the flash memory 1918 of the removable media device 1904. The open command may call a dll from the redirection module 1910 which causes a determination of whether the user is authorized to access the file (e.g., based on a password or other identifying information). The open command may also call a dll which causes a virus scan of the file prior to delivery of the file. Once these functions are performed, the redirection module 1910 may return control back to the operating system (e.g., the operating system performs the open file command to open a file in the flash memory 1918).

In one example, the redirection module 1910 may intercept a request for data from the flash memory 1918 of the removable media device 1904 from the operating system 1908. The redirection module 1910 may determine if access to the data is permitted and may scan the data for viruses and/or confidential content. If access is denied, the redirection module 1910 may replace the normal “open” command from the operating system 1908 with a notice that access to data is denied or that the data is not found. If access to data is granted, the redirection module 1910 may allow the normal “open” command form the operating system 1908 to open a file in the flash memory 1918 of the removable media device 1904.

In various embodiments, the redirection module 1910 may perform user authentication as well as content screening. In one example, the redirection module 1910 may identify a specific user through a user name, password, and/or other information received from the user. The redirection module 1910 may determine the user's rights based on the identification. For example, a user or a group of users may have access (e.g., view, read, write, modify, and/or create files) to some files but not others within the flash memory 1918. If the user attempts to perform a function but is not authorized, the redirection module 1910 may display a message denying the request or displaying an error message.

In some embodiments, the redirection module 1910 may also determine if the digital device 1902 has sufficient rights to view, read, write, modify, and/or create files in the flash memory 1918. In one example, the redirection module 1910 may identify a MAC address or other information that identifies the digital device 1902. The redirection module 1910 may then determine if the digital device 1902 identifier(s) are associated with rights to perform the called action(s). If user and/or the digital device 1902 have sufficient rights, the redirection module 1910 may allow one or more commands and/or functions. If there are insufficient rights, the redirection module 1910 may deny the requested command(s) and/or function(s).

The redirection module 1910 may also perform content screening. In various embodiments, the redirection module 1910 may perform malware scanning and/or correction of one or more files (e.g., a file called by the user) prior to allowing the user access. In one example, an authorized user may request a file from the flash memory 1918. Prior to allowing access, the redirection module 1910 may perform a scan of that file for malware. If the scan indicates that the file does not contain malware, the redirection module 1910 may allow the user to access the file. If the file contains malware, the redirection module 1910 may perform corrective action (e.g., remove the malware) and/or allow or deny the user access.

The redirection module 1910 may also scan one or more files in the flash memory 1918 for confidential information. If confidential information is found, the redirection module 1910 may determine if the user, application, and/or digital device 1902 is authorized to receive the confidential information. If the user, application, and/or digital device 1902 are authorized to access both a file and the confidential information within the file, the redirection module 1910 may allow the user access. Otherwise, the redirection module 1910 may deny access.

The application 1912 may be run locally on the digital device 1902 or run remotely by another digital device. In one example, the application calls for data from the removable media device 1904. The redirection module 1910 may determine the rights of the user and/or the application 1912 prior to allowing access. In some embodiments, even if the user is authorized, the application 1912 may not be authorized, and, as a result, the application 1912 may be denied access.

In various embodiments, the application 1912 may inject code from the removable media device 1904 into the digital device 1902. In one example, the digital device 1902 may execute the EXT-Login. exe 1922 from the removable media device 1904 which may provide the application 1912 as well as one or more dll(s). The application may inject code into the digital device 1902 by temporarily replacing one or more existing dll(s) with the dll(s) from the removable media device 1904 and/or enumerating services and redirecting one or more commands.

The hard drive 1914 may be any storage system configured to store information. The digital device 1902 may comprise the hard drive 1914. In one example, the operating system 1908 and file system 1906 are generated by executable code on the hard drive 1914. In another example, another digital device may comprise the hard drive 1914.

The removable media device 1904 may comprise the controller 1916, the flash memory 1918, and the login module 1920. The controller 1916 may be any controller that controls access to the flash memory 1918. The flash memory 1918 is any memory within the removable media device 1904. Although the flash memory 1918 is characterized by flash, the memory may be any kind or combination of computer readable media, including, but not limited to, a hard drive, tape, CD, DVD, memory stick, NAND memory, and/or NOR memory.

In some embodiments, the flash memory 1918 is encrypted and/or comprises sections that have different user rights. In one example, there may be a guest section whereby guests have limited rights (e.g., view and/or modify rights). Other sections may allow some users access but not others. Further, some sections may be reserved for only a single user (e.g., an administrator).

The login module 1920 detects when the removable media device 1904 is coupled with the digital device 1902 and executes instructions to generate the redirection module 1910. In some embodiments, the login module 1920 requires that the user provides a password and/or a user name prior to the generation of the redirection module 1910. The login module 1920 may then execute a set up program to generate the redirection module 1910 on the digital device 1902. In one example, when the removable media device 1904 is coupled to the digital device 1902, the digital device 1902 may see the removable media device 1904 as a CD. The login module 1920 may provide an extended login executable file (e.g., EXT-login. Exe 1922) which may be auto-run by the digital device 1902 which generates the redirection module 1910.

In various embodiments, upon coupling of the removable media device 1904 to the digital device 1902, the digital device 1902 mounts the removable media device 1904 as a CD drive with EXT-login.exe 1922. The digital device 1902 may execute the EXT-login.exe 1922 which launches new code (e.g., an application and one or more dll(s)). The application may perform code injection into memory. As a result, data to be retrieved from or data saved to the removable media device 1904 may be intercepted.

In various embodiments, there is no installation process of any of the new code in the operating system 1908. When the removable media device 1904 is removed, the injected code may be terminated and interception is ended.

In various embodiments, the administrator of the removable media device 1904 (e.g., the owner may be an administrator), may access a management tool that allows the administrator to create different policy sets, define users, groups, and assign a policy set to a user or group. In some embodiments, the management tool allows the administrator to change security policies 2010 (e.g., update, modify, create, delete, view, and save security policies). The administrator, in some embodiments, may also be able to access the removable media device 1904 and access or log-on the removable media device 1904 to view file operations, user access, and/or alerts.

FIG. 20 is a block diagram of the redirection module 1910 in an embodiment. The redirection module 1908 comprises an interceptor 2002, a security engine 2004, a user authentication module 2006, a content filter 2008, and security policies 2010. The interceptor 2002 is configured to redirect commands from and/or to the operating system 1908 or the file system 1906. In one example, the login module 1920 temporarily replaces one or more commands and/or dlls from the operating system 1908 when the removable media device 1904 is coupled to the digital device 1902. When one of the replaced commands and/or dlls are called, the interceptor 2002 redirects one or more functions through the redirection module 1908.

The security engine 2004 controls the redirection module 1908. The security engine 2004 may require that a user is authenticated to perform a desired function (e.g., interact with a file in the flash memory 1918 of the removable media device 1904). The security engine 2004 may also perform various functions such as scan for malware in the data contained within the flash memory 1918.

The user authentication module 2006 may require that the user provide at least a password before access to the flash memory 1918 is granted. In various embodiments, the user authentication module 2006 determines the rights for a user based on the password, other user identifier, or any combination of a password and other user identifiers. A user may have guest rights, limited user rights, or administrator rights. The flash memory 1918 may be divided into different sections. Each section may comprise data that is only accessible (e.g., viewed and/or modified) by a user with authentic user rights. For example, a guest may only have access to a guest section of the flash memory 1918. A user with limited user rights may only have access to a section associated with that user and/or the guest section. The administrator may have access to all sections of the flash memory 1918.

Guest rights are very limited rights which may allow access to a “public” or guest area of the flash memory 1918. For example, a user with guest rights may be able to access a limited number of files in the flash memory 1918 that is available to all users. In some embodiments, a guest may only be able to save files to the guest area of the flash memory 1918.

Limited user rights allow a user access to a section of the flash memory 1918 that is associated with their password and/or other user identifier. For example, a first user with limited user rights may be allowed to access a section of the flash memory 1918 that is associated with the first user. The first user may not be allowed to access, view, right, and/or modify a file in a different section of the flash memory 1918.

Administrator rights may allow the user to access all or some of the sections of the flash memory 1918. Although the flash memory 1918 is characterized as being divided into sections, those skilled in the art will appreciate that the flash memory 1918 may not be divided into physical or logical sections, but data may be associated with one or more user rights which determines the rights of the user based on their authentication (e.g., password or other identifiable information).

In various embodiments, the user authentication module 2006 associates one or more policy sets with the user and/or application. A policy set may associate one or more user identifiers with one or more rights. The policy set may identify authorized and/or not authorized file operations by user or a group of users. In one example, user X may be allowed to read and write data from file A but not allow to view content in file B. In another example, a group including users Y and Z may be allowed to read data from file C but not allowed to write to file A. The policy sets may identify user details, user type, user passwords and may include a group of users.

The content filter 2008 may be configured to scan for malware, perform firewall functions, or scan data stored within the flash memory 1918 for confidential information. In various embodiments, the security engine 2004 may determine that a user is authorized to access a file of the flash memory 1918 through the user authentication module 2006. Before data is provided to the user or data is allowed to be stored in the flash memory 2006, the content filter 2008 may scan the data for malware. If malware is identified the content filter 2008 may take corrective action (e.g., quarantine the file, remove the malware, scan for damage, notify the user and/or log the event). In one example, the content filter 2008 is configured to deny a user access to data if malware is detected. In another example, the content filter 2008 may refuse to store data in the flash memory 1918 if the data contains malware. Those skilled in the art will appreciate that the content filter 2008 may take any number of actions.

The content filter 2008 may also scan for confidential information within the data being retrieved from or saved to the flash memory 1918. In one example, the content filter 2008 scans the data for the name of confidential projects and/or the terms “confidential information,” “proprietary information,” or “trade secret” within the document. If confidential information is identified (e.g., the content filter 2008 scans a word processing document for confidential information), the content filter 2008 may determine if the user has access to that confidential information (e.g., via the user authentication module 2006). If the user is not allowed access. The user may be denied the file from the flash memory 1918 or refused to store the data. The content filter 2008 may also log the event and/or send a message to an administrator or other user to indicate that confidential information may be compromised.

The security policies 2010 may provide instructions and data to the security engine 2004, the user authentication module 2006, and or the content filter 2008. In one example, the security policies 2010 may contain user identifiable information as well as the rights that each user is allowed. In one example, the user authentication module 2006 may identify the user based on the password received from the user and a comparison of the password with records stored within the security policies 2010. The security policies 2010 may comprise the passwords (and/or other user identifiable information) as well as the user rights for one or more users of the removable media device 1904.

The security policies 2010 may also direct the content filter 2008. In some embodiments, the security policies 2010 comprise virus definitions or other resource files that allow the content filter 2008 to scan for malware and/or confidential data. The security policies 2010 may also direct the content filter 2008 to take corrective action, indicate who to contact and identify who to content under different circumstances. The security policies may comprise preferences and settings to control malware and confidential information scanning and/or corrective action.

FIG. 21 is a data flow diagram in an embodiment. The injected dll(s) may be implemented in one or more operating system 1908 functions. After the dll(s) are injected, an implemented function may be called instead of an operating system 1908 function. Criterions may be defined, according to predetermined actions when the function is called. In some embodiments, criterions are retrieved after the dll injection (e.g., the criterions may be retrieved from the removable media device 1904).

In step 2102, a user calls an operating system function. The user may be the user of the digital device 1902 or the user of an application that calls the operating system function. In step 2104, the operating system function call is received by the operating system 1908.

In step 2106, the interceptor 2002 of the redirection module 1908 intercepts the function call and determines if the function is a redirection function. In some embodiments, the interceptor 2002 may intercept the function call before the operating system receives the function call. If the interceptor 2002 determines that that the function call is to be redirected, the security engine 2004 receives the function calls and performs a predetermined action in step 2108.

The predetermined action may be any kind of action. In some embodiments, the security engine 2004 confirms that the user is authorized to perform an action (e.g., retrieve a file, view a file, or save data to the removable media device 1904). As discussed herein, the security engine 2004 may identify the user via a password and determine if the user associated with the password has rights associated with the desired action. If the user has the required rights, the security engine 2004 may pass the function call to the operating system 1908 and/or the original dlls of the operating system 1908. If the user does not have the required rights, the security engine 2004 may notify the user that the request is denied, notify the user that data is not found, and/or log the event.

The security engine 2004 may also perform any number of predetermined actions including scanning for malware prior to data being stored in the removable media device 1904, prior to the contents of the removable media device 1904 being changed, and/or prior to the contents of the removable media device 1904 being retrieved. In some embodiments, the security engine 2004 may scan data to be changed, retrieved, or stored for confidential information. If confidential information is found, the security engine 2004 may confirm that the user associated with the password or other user identifier(s) has rights to the confidential information. If the user has the necessary rights, the security engine 2004 may allow the user to perform various functions (e.g., view, change, or save data). If the user does not have the necessary rights, the security engine 2004 may notify the user that the request is denied, notify the user that data is not found, and/or log the event.

In step 2110, the security engine 2004 determines if the performed action(s) in step 2108 were to replace the function call of the original operating system function or whether the actions were to be performed in addition to the original function. For example, the security engine 2004 may require that all files retrieved from the removable media device 1904 are to be scanned for malware prior to opening. In this example, the security engine 2004 scans the desired file for malware before passing the original “open command” back to the operating system for normal processing (e.g., the scanned file is retrieved by the operating system 1908). In some embodiments, the security engine 2004 determines that the performed action(s) replace the original function call. For example, the security engine 2004 may determine that the user does not have rights to the desired data on the removable media device 1904 and does not allow the operating system 1908 to receive the function call.

If the function call is not a redirected function or the performed action by the security engine 2004 does not replace the original function, the function call passes to the operating system 1908 in step 2112 which processes the call.

FIG. 22 is a flow diagram of data flow of code injection in an embodiment. In step 2202, the digital device 1902 detects coupling of the removable media device 1904. In some embodiments, the user couples the removable media device 1904 to the digital device 1902. The digital device 1902 may attempt to mount the removable media device 1904 and automatically run the EXT-login.exe 1922 (e.g., the digital device 1902 may identify the removable media device 1904 as a compact disc and auto-run the EXT-login.exe 1922).

In step 2204, an application and one or more dll(s) may be copied from the removable media device 1904 to the digital device 1902. In some embodiments, the application sets up the redirection module 1908. In other embodiments, the dll(s) comprise the redirection module 1908 or the application and the dll(s) may comprise the redirection module 1908. Those skilled in the art will appreciate that there may be any number of applications.

In step 2206, the digital device 1902 executes the application. In step 2208, the application enumerates one or more user processes. In one example, the application comprises a list of relevant user processes. In some embodiments, existing user processes are replaced with new processes by the application(s). In various embodiments, new user processes are associated with existing user processes thereby allowing control to be redirected and/or new functions added to existing functions.

In step 2210, the application injects one or more dll(s) to the enumerated user processes. In step 2212, the user processes are monitored (e.g., by the redirection module 1908). When enumerated processes are called, the redirection module 1908 may authenticate the user to confirm rights and/or provide content filter functions (e.g., malware scanning or firewall functions).

In step 2214, the user may indicate that the removable media device 1904 is to be removed. Prior to removal, the application may unload injected dll(s) from the user processes. In some embodiments, the application may unload injected dll(s) upon detection that the removable media device 1904 has been physically decoupled from the digital device 1902.

FIG. 23 is a flow diagram of a method for dll injection in an embodiment. In one example, FIG. 23 provides additional detail for the method step of injecting one or more dll(s) to the enumerated user processes discussed in step 2210 of FIG. 22. In some embodiments, a user process may intercept a function call and then perform a new instruction or new code. Subsequently, the original call and/or dll may be returned.

In step 2302, the application injects one or more dll(s) to one or more user processes. In step 2304, a user or application calls an operating system 1908 “open” function (e.g., the user or application attempts to open a file). In step 2306, a user process associated with an injected dll may redirect the function and determine if the function will be allowed or if another action may be taken. If the function is associated with an injected dll, the redirection module 1908 may determine whether to allow the function. In one example, the user authentication module 2006 may retrieve a security policy 2010 associated with the user to determine if the user has rights associated with the file the user wishes to open. If the rights exist, the redirection module 1908 may allow the user to open the file (e.g., allow the operating system 1908 to receive the open function call) in step 2312.

If the user redirection module 1908 determines if the user or application has insufficient rights, the redirection module 1908 may reject the user open file request and throw and error message in step 2310.

Those skilled in the art will appreciate that, in some embodiments, a determination of whether the function call is a redirected function is optional. In some embodiments, the function call may call one or more dlls that have been injected by the removable media device 1904 to temporarily replace one or more dlls of the operating system. When the temporary replacement dll is called, the predetermined action may take place.

FIG. 24 is a block diagram of an exemplary digital device 1902. The digital device 1902 comprises a processor 2402, a memory system 2404, a storage system 2406, an input/output interface 2408, and a communication network interface 2410 communicatively coupled to a communication channel 2412. The processor 2402 is configured to execute instructions (e.g., applications). In some embodiments, the processor 2402 comprises circuitry or any processor capable of processing the executable instructions.

The memory system 2404 comprises computer readable media that stores data. Some examples of computer readable media within the memory system 2404 include storage devices, such as RAM, ROM, RAM cache, virtual memory, etc. In various embodiments, working data is stored within the memory system 2404. The data within the memory system 2404 may be cleared or ultimately transferred to the storage system 2404.

The storage system 2406 includes any storage configured to retrieve and store data. Some examples of computer readable media of the storage system 2406 include flash drives, hard drives, optical drives, and/or magnetic tape.

The input/output (I/O) interface 2408 is any device that inputs data (e.g., mouse and keyboard). In some embodiments, the I/O interface 2408 comprises a port such as a USB or firewire port configured to couple to a removable media device. Those skilled in the art will appreciate that the storage system 2406 may be optional.

The communication network interface (com. network interface) 2410 may be coupled to a network and/or bus via the link 2414. The communication network interface 2410 may support communication over an Ethernet connection, a serial connection, a parallel connection, and/or an ATA connection. The communication network interface 2410 may also support wireless communication (e.g., 802.11 a/b/g/n, WiMax, LTE, WiFi). It will be apparent to those skilled in the art that the communication network interface 2410 can support many wired and wireless standards.

It will be appreciated by those skilled in the art that the hardware elements of the digital device 1902 are not limited to those depicted in FIG. 24. A digital device 1902 may comprise more or less hardware, software and/or firmware components than those depicted (e.g., drivers, operating systems, touch screens, biometric analyzers, etc.). Further, hardware elements may share functionality and still be within various embodiments described herein. In one example, encoding and/or decoding may be performed by the processor 2402 and/or a co-processor located on a GPU (i.e., Nvidia).

The foregoing description of the preferred embodiments of the present invention is by way of example only, and other variations and modifications of the above-described embodiments and methods are possible in light of the foregoing teaching. Although the network sites are being described as separate and distinct sites, one skilled in the art will recognize that these sites may be a part of an integral site, may each include portions of multiple sites, or may include combinations of single and multiple sites. The various embodiments set forth herein may be implemented utilizing hardware, software, or any desired combination thereof. For that matter, any type of logic may be utilized which is capable of implementing the various functionality set forth herein. Components may be implemented using a programmed general purpose digital computer, using application specific integrated circuits, or using a network of interconnected conventional components and circuits. Connections may be wired, wireless, modem, etc. The embodiments described herein are not intended to be exhaustive or limiting. The present invention is limited only by the following claims. 

The invention claimed is:
 1. A method comprising: detecting a removable media device being coupled to an external device port of a digital device, the digital device having an operating system and a file system, the removable media device having a login module; causing, after detecting the removable media device being coupled to the external device port of the digital device, at least a portion of redirection code to be generated on the digital device by the login module of the removable media device, the redirection code including an interceptor, a data security policy, and a data security process; intercepting, using the interceptor, a first function call to the operating system or the file system of the digital device before the first function call is executed by the operating system or the file system, the first function call including a request of the operating system or the file system to retrieve data from or write data to the removable media device, the first function call being initiated by a particular user or a particular application; and performing a set of one or more second function calls in response to intercepting the first function call, the set of one or more second function calls not including the first function call, the set of one or more second function calls including a data-security-based second function call, the data-security-based second function call causing the steps of: executing the data security process, the data security process determining whether the particular user or the particular application is authorized to retrieve the data from or write the data to the removable media device, and thus whether to allow the first function call based at least on results of the data security process; and allowing the operating system or the file system to execute the first function call in response to a determination to allow the first function call.
 2. The method of claim 1, further comprising selecting the data security policy from a plurality of data security policies based, at least in part, on a password, wherein different passwords are associated with different access rights defined by different data security policies.
 3. The method of claim 1, wherein the data security process filters content of the data.
 4. The method of claim 3, wherein the data security process filters the content by scanning the data for confidential information.
 5. The method of claim 1, wherein causing the at least a portion of the redirection code to be generated comprises injecting the at least a portion of the redirection code into the digital device by temporarily replacing one or more dynamic-link libraries (dlls) within the digital device.
 6. The method of claim 1, wherein causing the at least a portion of the redirection code to be generated comprises injecting the at least a portion of the redirection code into the digital device by enumerating user processes of the digital device and injecting dlls into the enumerated user processes.
 7. The method of claim 1, further comprising receiving a shut down command and removing the at least a portion of the redirection code in response to the shut down command.
 8. The method of claim 1, further comprising removing the at least a portion of the redirection code in response to a detection that the removable media device is no longer coupled to the digital device.
 9. A system comprising: an operating system of a digital device configured to detect a removable media device being coupled to an external device port of the digital device; one or more processors; memory coupled to the one or more processors, the memory storing instructions to instruct the one or more processors to implement: a login module configured to cause, after detecting the removable media device being coupled to the external device port of the digital device, at least a portion of redirection code to be generated on the digital device, the redirection code including an interceptor, a data security policy, and a data security process, the interceptor configured to intercept a first function call to the operating system of the digital device before the first function call is executed by the operating system, the first function call including a request of the operating system to retrieve data from or write data to the removable media device, the first function call being initiated by a particular user or a particular application, the data security process configured to perform a set of one or more second function calls in response to intercepting the first function call, the set of one or more second function calls not including the first function call, the data security policy configured to evaluate data on the removable security device for malware, and the data security policy configured to determine whether to allow the first function call based at least on results of the data security process.
 10. The system of claim 9, wherein the login module is further configured to select the data security policy from a plurality of data security policies based, at least in part, on a password, wherein different passwords are associated with different access rights defined by different data security policies.
 11. The system of claim 9, wherein the login module is further configured to filter content of the data.
 12. The system of claim 11, wherein filtering the content comprises scanning the data for confidential information.
 13. The system of claim 9, wherein the login module configured to cause the at least a portion of the redirection code to be generated comprises the login module configured to inject the at least a portion of the redirection code into the digital device by temporarily replacing one or more dynamic-link libraries (dlls) within the digital device.
 14. The system of claim 9, wherein the login module configured to cause the at least a portion of the redirection code to be generated comprises the login module configured to inject the at least a portion of the redirection code into the digital device by enumerating user processes of the digital device and injecting dlls into the enumerated user processes.
 15. The system of claim 9, wherein the digital device is configured to receive a shut down command and remove the at least a portion of the redirection code in response to the shut down command.
 16. The system of claim 9, wherein the digital device is configured to remove the at least a portion of the redirection code in response to a detection that the removable media device is no longer coupled to the digital device.
 17. A non-transitory computer readable media comprising instructions, the instructions executable by a processor to perform a method, the method comprising: detecting a removable media device being coupled to an external device port of a digital device, the digital device having an operating system and a file system, the removable media device having a login module; causing, after detecting the removable media device being coupled to the external device port of the digital device, at least a portion of redirection code to be generated on the digital device by the login module of the removable media device, the redirection code including an interceptor, a data security policy, and a data security process; intercepting, using the interceptor, a first function call to the operating system or the file system of the digital device before the first function call is executed by the operating system or the file system, the first function call including a request of the operating system or the file system to retrieve data from or write data to the removable media device, the first function call being initiated by a particular user or a particular application; and performing a set of one or more second function calls in response to intercepting the first function call, the set of one or more second function calls not including the first function call, the set of one or more second function calls including a data-security-based second function call, the data-security-based second function call causing the steps of: executing the data security process, the data security process determining whether the particular user or the particular application is authorized to retrieve the data from or write the data to the removable media device, and thus whether to allow the first function call based at least on results of the data security process; and allowing the operating system or the file system to execute the first function call in response to a determination to allow the first function call.
 18. The method of claim 1, wherein the data security process includes an authentication process.
 19. The method of claim 1, wherein the data security process includes a malware detection process.
 20. The system of claim 9, wherein the data security process includes an authentication process.
 21. The system of claim 9, wherein the data security process includes a malware detection process. 